Expansion drill



Mar. 27, 1923. I 1,450,053.

j C. L. STICKNEY. EXPANSION DRILL. ILEDU 1 1921. /z'

ATTORNEY.

Patented Mar. 27, 1923.

UNITED STATES PATENT OFFICE.

CHARLES L. STICKNEY, OF PRESCOTT, ARIZONA, ASSIGNOR TO EXPANSION DRILL COMPANY, OF PRESCOTT, ARIZONA.

EXPANSION DRILL.

Application filed July 11, 1921. Serial No. 483,931.

To all whom it may concern:

Be it known that I, CHARLES L. STIoKNnY,

a citizen of the United States, residing at Prescott, in the county of Yavapai and State of Arizona, have invented certain new and useful Improvements in an Expansion Drill, of which the following is a specification.

This invention relates to improvements in expanding drills of the class more particularly employed in deep well operations, and

has for one of its objects to simplify and improve the construction and decrease the expense of manufacture.

Another object of this invention is to produce a device of this character with the cutter members alike and interchangeable, thereby facilitating the renewal of impaired arts. I

p Another object of the invention is to provide a device of this character in which the parts are few in number, and can be produced by drop forging or by similar rapid and inexpensive operations.

With these and other objects in view the invention consists in certain new and novel features of construction as hereinafter shown and described and then specifically pointed out in the claims, and in the drawings illustrative of the preferred embodiment of the invention Figure 1 is a side elevation with the cutting members in withdrawn position.

Fig. 2 is an elevation with the stock and pivot pin in section, and with the cutters in withdrawn position.

Fig. 3 is a view similar to- Fig. 2 with the cutters in distended position.

Fig. 4 is a transverse section on the line Jr-4 of Fig. 1.

Fig. 5 is a transverse section on the line 55 of Fig. 1.

Fig. 6 is a transverse section on the line 66 of Fig. 1.

Fig. 7 is an edge view from the inside of one of the cutter members.

Fig. 8 is a side elevation of one of the cutter members.

Fig. 9 is an edge View from the outside of one of the cutter members.

The improved device comprises a stock 10 adapted to be attached to a drill rod or cable and bifurcated to form coacting j awsf 11 and 12 in spaced and parallel relation and preferably with their outer ends reversely bevelled as represented at 13 and 14.

At the juncture of the jaws l1 and 12 and the stock 10, a recess 15 is formed with coacting seats 16 and 17 forming the bottom of the recess. v j

A relatively heavy pin 18 connects thelj aw portions 11 and 12 as shown. i

Movably disposed between the jaw portions are the cutter members of the improved device, and as they are precisely alike and therefore interchangeable, the description of one will suflice for both.

Each of the cutter members comprises a head portion 19 rounded to bear respectively in the seats 16 and 17, and each laterally enlarged at the other end as at 20 with a bevelled cutting edge 21 and a bevelled lateral shoulder 22 coacting with the bevelled ends 13 and 14 of the jaw portions when the cutters are in distended position.

Each cutter member is also formed with a half bearing 23 and a half socket 24, the half bearings overlapping and engaging face to face with the half bearing of one member engaging in the socket 24 of the other member, as represented in Fig. 4, to prevent lateral displacement of the cutters.

By this means the cutter members are swingingly coupled between the jaw portions.

Each cutter member is likewise formed with another half bearing 25 to engagethe pin 18 from opposite sides, as shown in Figs. 2 and 5.

Each cutter member is also provided with a bearing rib 26 to engage the confronting faces of the enlarged portions of the cutter members, and thus reduce the friction and consequent wearing of the parts.

The ribs likewise interlock when the cutter members are distended and thus limit the outward movement and prevent the cutter members from becoming separated during the operation.

When the drill device is forced downwardly against the rock to be drilled, the cutter members are caused to expand by the engagement of the head portions 19 with the curved faces 16 and 17 of the recess and the contact of the pin 18 with the portions: of the cutters in advance of the pin, and distend the cutting ends of the cutter members as shown in Fig. 3, to cause them to drill a hole much larger than the body portion 10 and the jaws 11 and 12.

The device is simple in construction, can be inexpensively manufactured mostly by drop forgings and operates effectually for the purposes described.

The preferred embodiment of the invention is disclosed in the drawings and setforth in the specification, but it will be understood that modifications within the scope of the claims may be made in the construction without departing from the principle of the invention or sacrificing any-of its advantages.

Vhat is claimed, as new is 1. In an implement of the class described, a mandrel bifurcated to produce spaced jaws reversely bevelled and coupled by a transverse pin, the mandrel being recessed at the inner ends of the jaws with coacting seats in the recess, coacting cutter members each formed with a head portion engaging respectively in the seats and with outer cutting ends and lateral shoulders to be engaged by the bevelled ends of'thejaws when the same are distended, said jaws having half sockets to receive the coupling pin, and means for swingingly coupling said cutter members.

2. In an implement of the class described, a mandrel bifurcated to produce spaced jaws and recessed at the inner ends of the jaws with coacting seats in the recess, a coupling pin extending transversely through said jaws, coacting cutter members each formed.

with a head portion engaging respectively in the seats and with outer cutting ends, said jaws having half sockets to receive the coupling pin, and overlapping lugs to prevent lateral displacement of the cutters.-

In testimony whereof, I al'fix my signature hereto, a

CHARLES L. STICKNEY. 

